JPS61272581A - Muddy material indirect drier - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in an indirect drying apparatus for drying muddy materials such as sewage sludge, stale urine sludge, and food muddy materials.

(Prior art) Generally, when drying muddy materials such as sewage sludge, there are two methods: a direct drying method in which combustion gas or high-temperature air is brought into direct contact with the muddy material, and a method in which the muddy material is indirectly dried using steam or heat transfer liquid. There is an indirect drying method that involves heating.

In the indirect drying method, when drying food slurry, there is no dirt from the slurry compared to the direct drying method, and when drying sewage sludge, etc., a large amount of odor-containing exhaust gas is not generated. It has the advantage of being extremely hygienic,
Widely used.

6 to 9 show a conventional indirect drying device using an indirect drying method, and the device includes a supply port 16 and a discharge port 1.
7 and a jacket 18 formed on the outer periphery; a plurality of hollow shafts 20 which are rotatably arranged in parallel while penetrating the casing 19; It is made up of hollow heating disks 21 and the like that are arranged at regular intervals along the line and in a state of inconsistency with each other, and are installed in a slightly inclined state so that the discharge port 17 side is lower. In addition, 22 is a transmission device, 23
is a cooler, 24 is a preheater, and 25 is a suction blower.

Thus, the highly water-containing slurry A' is introduced into the casing 19 from the supply port 16 and is discharged from the discharge port 17 as a dry material. This slurry usually has a moisture content of 75-80%.
It is dried to 0-40%.

On the other hand, each hollow shaft 20 rotating at a constant speed in a predetermined direction is supplied with water vapor B' or high-temperature heat transfer liquid D' from one end.
These flow into the hollow heating disk 21 to heat the slurry, and are discharged from the other end of the hollow shaft 20 as condensate or low-temperature liquid. Further, steam B' and high temperature heat transfer liquid D' are supplied to the jacket 18 from the inlet, and these are discharged from the outlet as condensate or low temperature liquid.

In addition, in the above device, water vapor generated within the casing 19 is cooled and condensed, and only air is circulated within the casing 19, so that odor-bearing water vapor is not discharged to the outside and can be treated in an extremely hygienic manner.

However, although the sludge A' varies depending on its physical properties, at a certain moisture percentage, the sludge A' becomes very sticky, and as shown in FIG. Sometimes.

Therefore, in the conventional indirect drying apparatus, there are problems in that the heat transfer loss increases significantly and the driving horsepower becomes overloaded, making it difficult to operate.

(Problems to be Solved by the Invention) The present invention was devised to solve the above-mentioned problems, and its purpose is to prevent even highly adhesive mud from sticking to equipment. To provide an indirect drying device for sludge that can prevent the above problems and also enables smooth operation.

(Means for Solving the Problems) Generally, when transporting highly adhesive substances, a screw conveyor with ribbon-shaped blades is used.

This is said to be able to prevent substances from adhering to the blade because the shaft and blade attachment are mostly hollow at the root, where substances tend to adhere to them.

The indirect mud drying device of the present invention was developed based on the above knowledge, and includes a casing having a mud supply port and a discharge port, and a jacket formed on the outer periphery through which a heat medium flows. , a plurality of hollow shafts are rotatably arranged in parallel through the casing, through which a heat medium flows, and each hollow shaft is arranged concentrically at regular intervals along the axial direction, so that each hollow shaft is arranged in parallel with the other. A donut-shaped hollow heating disk, a connecting pipe interposed between the hollow shaft and the inner circumferential surface of the hollow heating disk to communicate the two, and a connecting pipe disposed on the outer circumferential surface of the hollow heating disk. It is characterized in that it is equipped with blades that move the sludge toward the discharge port and scrape the outer circumferential surface of the hollow shaft and the inner surface of the casing.

(Function) In the indirect drying device, the highly water-containing slurry is introduced into the casing from the supply port, and is heated by steam or high-temperature heat transfer liquid in the hollow shaft, hollow heating disk, and jacket. It is discharged from the outlet as a dry substance.

On the other hand, water vapor or high-temperature heat transfer liquid is supplied from one end to a hollow shaft rotating at a constant speed in a predetermined direction.
These become condensate or low temperature liquid and are discharged from the other end. Steam or high-temperature heat transfer liquid is also supplied to the jacket, and these are discharged as condensate or low-temperature liquid.

In addition, since the mud is forcibly transferred to the discharge port side by the action of the blades, the mud in the gap between the hollow shaft and the hollow heating disk is constantly replaced with new mud, and the mud in the gap is constantly replaced with new mud. It is not resistant to muddy substances. In addition, since the blades scrape the outer circumferential surface of the hollow shaft and the inner surface of the casing,
Sludge does not adhere to these.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a schematic vertical cross-sectional view of an indirect drying device for sludge according to an embodiment of the present invention. It is installed at a slight incline so that the outlet side is lower.

The casing 1 has a substantially cylindrical shape with a slurry supply port 5 at one end and a mud discharge port 6 at the other end, and a jacket 7 through which a heat medium flows is formed on the side and bottom surfaces. ing.

A pair of hollow shafts 2 are arranged in parallel along the longitudinal direction of the casing 1 while passing through the casing 1, and are rotatably supported by the casing 1. Also, hollow shaft 2
A transmission device 8 for rotating each hollow shaft 2 in the direction of the arrow shown in FIG. 2 is provided at one end of the shaft.

The hollow heating disks 3 have a donut shape, and are disposed concentrically with each hollow shaft 2 at regular intervals along the axial direction, as shown in FIGS. 3 and 4, and are spaced apart from each other [ 1 state.

Further, a pair of connecting pipes 9 are interposed between the inner circumferential surface of the hollow heating disk 3 and the hollow shaft 2 to communicate the two.

In addition, when a heat medium such as water vapor flows through the hollow shaft 2 and the hollow heating disk 3, a partition plate 10 is installed near the connecting pipe 9 in the hollow heating disk 3 to partition the internal space, as shown in FIG. A bottom raising pipe 11 is provided inside the hollow shaft 2 and communicates with the connecting pipe 9.

On the other hand, a plurality of blades 4 are arranged at a constant inclination angle on the outer circumferential surface of the hollow heating disk 3, and these blades move the mud toward the discharge port, and also move the sludge toward the outer circumferential surface of the hollow shaft 2 and the casing. This is to scrape the inner surface of 1.

In addition, in FIG. 1, 12 is a cooler, 13 is a preheater, 1
4 is a suction blower.

Next, the operation of the indirect drying device will be explained.

The highly water-containing slurry A is introduced into the casing 1 from the supply port 5, is indirectly heated by the water vapor B flowing through the hollow shaft 2 and the hollow heating disk 3, and is discharged from the discharge port 6 as a dry material. Ru.

The water vapor generated within the casing 1 is then transferred to the cooler 12.
Only the air that has been condensed and heated in the preheater 13 is returned into the casing 1.

Note that the mud A is forcibly transferred to the discharge port side (in the direction of arrow A) as shown in FIG. The sludge is constantly replaced with new sludge, and the sludge does not stick inside the gap. Further, since the blades 4 have a constant inclination angle, the entire outer circumferential surface of the hollow shaft 2 can be scraped, and muddy substances will not adhere to the outer circumferential surface of the hollow shaft 2. Furthermore, since the blades 4 also scrape the inner surface of the casing 1, it is possible to prevent mud from adhering to the inner surface of the casing 1, and to actively move mud from the heat transfer surface to improve heat transfer efficiency. You can also do that.

However, since the side surface of the hollow heating disk 3 is close to the side surface of other hollow heating disks 3, and the outer circumferential surface of the hollow heating disk 3 is close to the inner surface of the casing 1, there may be mud on the side and outer circumferential surfaces. is becoming difficult to withstand.

On the other hand, water vapor B is supplied from one end into the hollow shaft 2, which is rotating at a constant speed in a predetermined direction. The water vapor B supplied into the hollow shaft 2 enters the hollow heating disk 3 through the bottom raising pipe 11 and the connecting pipe 9, as shown in FIG.
Here, heat is applied to the mud to form condensate, which accumulates at the bottom of the disk 3. The condensate C accumulated in the hollow heating disk 3 is pumped up by the partition plate 1o when the disk 3 rotates, and is pumped up by the partition plate 1o.
0 is in the upper position, the connecting pipe 9 and the bottom raising pipe 11
It is returned into the hollow shaft 2 through. This condensate water is prevented from returning into the hollow heating disk 3 by the bottom raising pipe 11a, flows inside the hollow shaft 2, and is discharged from the other end.

In addition, a heat medium such as water vapor B is introduced into the jacket 7 from one end.
Alternatively, high-temperature heat transfer liquid is supplied, which heats the slurry and then becomes condensate or low-temperature liquid and is discharged from the other end.

In the above embodiment, water vapor B is made to flow inside the hollow shaft 2 and the hollow heating disk 3, but in other embodiments, a high temperature heat medium liquid may be made to flow. In this case, a partition plate 1 is inserted into the hollow shaft 2 as shown in FIG.
5 is provided so that the high-temperature heat medium liquid flows inside the hollow heating disk 3 in a predetermined direction (in the direction of the arrow) and returns to the inside of the hollow shaft 2 again.

Further, in the above embodiment, the casing 1 is provided with a pair of hollow shafts 2, but in other embodiments, the casing 1 may be provided with four or six hollow shafts 2. .

Furthermore, in the above embodiment, the connecting pipe 9 and the partition plate IO
Although one pair is provided, in other embodiments, - or three or more may be provided.

(Effects of the Invention) As described above, the indirect drying device of the present invention has a donut-shaped hollow heating disk attached to a hollow shaft through a connecting pipe, and sludge is directed to the discharge port side on the outer peripheral surface of the hollow heating disk. As the blades are provided to scrape the outer circumferential surface of the hollow shaft and the inner surface of the casing, a gap is formed at the root of the hollow shaft and the hollow heating disk, and the mud in the gap is removed by the blades. The hollow shaft and disc attachment, which were traditionally most susceptible to mud adhesion, are constantly replaced with new mud that has been transferred due to the action of can be reliably prevented.

In addition, since the blades scrape the outer peripheral surface of the hollow shaft, it is possible to reliably prevent mud from adhering to the hollow shaft.

Furthermore, since the blades also scrape the inner surface of the casing,
It is possible to reliably prevent mud from adhering to the inner surface of the casing, and to actively move mud to greatly improve heat transfer efficiency.

Moreover, if a gap is formed at the root of the connection between the hollow shaft and the hollow heating disk, this location will be located on the inner peripheral surface of the hollow heating disk.
The outer circumferential surface of the hollow shaft and the outer circumferential surface of the connecting pipe, which face the inner circumferential surface of the disc, increase the heat transfer area compared to conventional ones.
Thermal efficiency can be improved.

In this way, the indirect drying device of the present invention can prevent mud from adhering to each device. As a result, thermal efficiency can be greatly improved, and smooth operation can be performed without overloading the drive horsepower.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view of an indirect drying device for sludge according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view taken along the line lI--line in FIG.
3 is a sectional view taken along the line T in FIG. 2, FIG. 4 is a longitudinal sectional view of the hollow heating disk, and FIG. 5 is a longitudinal sectional view of the hollow heating disk showing another embodiment. Fig. 6 is a schematic vertical sectional view of a conventional indirect drying device for sludge, Fig. 7 is an enlarged sectional view taken along the line ■-■ in Fig. 6, and Fig. 8 is a sectional view taken along the line ■-1 in Fig. 7. FIG. 9 is a partial side view of the hollow shaft and the hollow heating disk with mud adhered thereto. l is the casing, 2 is the hollow shaft, 3 is the hollow heating disk, 4 is the blade, 5 is the supply port, 6 is the discharge port, 7 is the jacket, 9 is the connecting pipe, 10.15 is the partition plate, A is the mud B is steam, Ct condensate, and D is high-temperature heat transfer liquid. Patent Applicant Tarima Co., Ltd. President Fuku 1) Junkichi Figures 3 and 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (3)

[Claims] (1) A jacket (7) having a supply port (5) and a discharge port (6) for the slurry (A) and through which a heat medium flows around the outer periphery
A casing (1) formed with a casing (1), a plurality of hollow shafts (2) that are rotatably arranged in parallel through the casing (1) and through which a heat medium flows, and a shaft that is concentric with each hollow shaft (2). Between donut-shaped hollow heating disks (3) that are arranged at regular intervals along the core direction and are in a state of inconsistency with each other, and the hollow shaft (2) and the inner circumferential surface of the hollow heating disks (3). A connecting pipe (9) is provided to connect the two, and a connecting pipe (9) is provided on the outer circumferential surface of the hollow heating disk (3) to move the mud to the discharge port side and also to transfer the mud to the hollow shaft (2). A blade (4) for scraping the outer peripheral surface and the inner surface of the casing (1)
A sludge indirect drying device characterized by comprising: (2) At least one partition plate (2) that converts the heat medium into water vapor (B) and pumps up the condensate (C) accumulated inside the hollow heating disk (3) and returns it to the hollow shaft (2). 10) The indirect mud drying apparatus according to claim 1, characterized in that the device has a structure comprising: 10). (3) The heat medium is a high temperature heat medium liquid (D), and the hollow shaft (2) is connected to the hollow heating disk (3), and the high temperature heat medium liquid is a hollow heating disk (3).
The indirect drying device for sludge according to claim 1, characterized in that it has a structure including a partition plate (15) so that the flow inside the hollow shaft (2) flows in a predetermined direction and returns to the hollow shaft (2).